Angle dental handpiece



Aprl 12, 1932. P. R. SKINNER ANGLE DENTAL HANDPIECE Filed Feb. l2, 1931Patented, Apr; `12; A1932 PATENT- maar nrsxmnnnron AMSTERDAM, NEW romsAirmanV :DENTAL Hannrrncn Applicatonjled February'lZ, 1981'. Serial-1X0`515,2862

Thisfinvention relates to means for detach: ably connecting a tool to anangle dental handpiece.

In devices for kthe purpose as. commonly cause the usual fastening meansis attached 10 to a non-rotatable part of the handpiece, andprojectsinto a Icircumferential groovein theV rotating tool orotherwise,enga-ges theA tool, Consequently,.after any considerable use,the securing 'means' becomes Worn by'reasOn.v Of

*i5 frictional' Contact With.` the tool", thetooll is less rigidly held,and finallythe Securing means becomes inoperative. Any: loosening ofthetool in its holder allows of= 1nore or less Wabbling of the tool andimpairs its effectiveness, and frequently in practice, be-

causeof 'the Wearing out` ofi 1 the attaching means, a tool is releasedinthe mouth .ofva patient being oper-ated upon, and there: is vdangerofthe tool lodging in; the. throat Of the patient or of being swallowed;l

The principal object of thezpresent inveliF Y tion isl to providemeans:forfdetachably Securing-a; tool in: an. angle dental handpiece, wherebyWhen infuse/the tool isi directly Secured4 toy the parts by whichthetool isI ros tated, thusk dispensingwith any intermediate deviceuponwhichfri'ctionis imposed. Furf ther objects are to, provideatta'chingmeans of the kind described in which a tool may be eithersecured or released, by easy and rapidey manipulation of the partsemployed, and which is adapted. for use in connection with toolsvhavingthestandard formof shank. Another object is to provide attachingmeans yWhich shall positively engage a. tool', When the latter is inposition for use, in a manner to avoid accidental Withdrawal ofthe tool;

The invention residesin the various'genel# cally and specifically novelfeaturesof construction and arrangement of parts substantially ashereinafter described and claimed. One form of'embodiment of theinvention is illustrated in the accompanying drawings. Figurel is alcentral vertical sectional view 59 of theyhead 'of' an anglehandpiece,` having therein thenovel meansafol'. attaching a tool, atoolbeing: shown inattached position.

Y Figure@ isa top planvievv of a head, showing the4 cap ley-Which theattaching means is released. .f f

Figure Sis a perspectiveview of the rotat ablesleeve through whichextends a cylindrical clutch by which a tool is detachably held, thesleeve having a bevel gear thereon.

y AFigurel is a; side view of the cylindrical clutchbyy-Which atoolisreceived and detachably held.

.Figure 5 is' a kside View. of a dental tool Y having a: shank. of thestandard form.

Figurel (iis aA side view: of a mandrel of a. form; to be engaged bytheimproved attaching means.

Y Figure 7 fis a viewshowing a modified form of the top of the clampingmember.

In thediavvings the head of,` a dental angle handpiece isindicated by 1and 2 indicates the usual rotatable sleeve,L ymounted in the head, andWhich has,vusually integral with it, apbevel pinion. Rotation of thesleeve is effected through aL bevel gear t, suitably driven, andmeshing-With the pinion 8. EX- tendingintothe sleeve is aproj ection 5,Which engages a tool receiving and engaging member? 6. when. thelatteris in position to extend *through the sleeve, to cause the tWo parts tonotate in unison. f e l The tubular member 6, which in usel is locatedin andprojects through, the sleeve 2, is made of'resilient metal, isprovided With the slot 7 `which extends from end to end ofthe member,receivingthe projection 5 from the ycollar-2, and which also is providedat one end withk one or more slits 8 `which permit of the easyvexpansionand contraction of such end. This slotted endV isin'ormally flaring inorder to permit of the ready introduction of the shank 9 ofthe toollO,andy it terminates in an enlargement 'or-collar' 1l Which abuts againstf Vthe lower end of the rotatablesleeve `2 to limit `the movement ofthetubular member 1 upwardly through the sleeve.

The shank 9 of the standard dental tool is abruptly reduced at itsoperative end, forme ing a circumferential shoulder l2., In complementwith this-,form of shank the extreme end of the clamping member 6 isformed with inwardly extending lips or extensions 13, which projectsubstantially at right angles to the inner face of the member. Therelative disposition ofthe respective parts is such that when a tool isintroduced into the handpiece, in a position for use, the lips orextensions of the clamping member, when in engaging locations, assumepositions immediately below the shoulder 12 of the tool shank,

and thus positively secure the tool in a man-kr ner to preventwithdrawal.

A dental mandrel, such as shown in Figure 6, which usually has a smoothcylindrical shank, can readily be adapted for use in connection with thedescribed securing means by providing it with a circumferential recess111, so located as to be entered by the lips or extensions when themandrel is operatively introduced into a handpiece.

Interposed between the rotatable sleeve 2 and the cylindrical member 6is a spring 15 the function of which is to maintain the parts in thepositions shown in Figure 1 of the drawings; that is, with the member 6drawn into the sleeve in a manner to contract the flaring end of suchmember. Any suitable form of spring may be used for the describedpurpose, and it may be disposed in various positions. As herein shown,it is in the form of a coil, one end of which bears on the upper end ofthe sleeve 2 and the other end against the lower face of a disk 16suitably secured to the upper end of the member 6. The disk has acentral opening receiving the member 6, and is held in place by a pin 17passing through the upper portion of the wall of the member, and havingits projecting ends bearing on the upper face of the disk. In placingthe spring in position, it is put under tension by compressing it, inorder that it may function normally to maintain the member 6 in aposition with its lower end drawn into the sleeve, and, therefore,contracted.

When it is desired to move the flaring lower end of the member 6downward to free it from the sleeve 2 and permit such end to expand, itis necessary to apply a small amount of force to the upper end of themember to overcome the tension of the spring 15. As a convenient meansof accomplishing this movement a cap 1S having a spring arm 19 issecured to the head 1 kof the hand piece by a screw 20, extends over theupper end of the member 6, and contacts with the latter.

The cap 18 not only serves when depressed to give the required movementto the member 6, but also covers and protects from dirt the upper end ofthe opening in the head in which the working parts of the devices arelocated, and gives the head a finished appeau ance.

The rotatable sleeve and the clamping member are retained in the head 1by a screw plug 21 having an opening therethrough for the passage of theshank of a tool.

The rotation of a tool which, in the standard form, has an indentationor liattened portion 22 at its end is effected in unison with part-s ofthe form hereinbefore described, by the juncture effected by theengagement of the projection 5 of the sleeve 2 with this tlattenedportion when the tool is introduced. Iut, as various constructions maybe used for properly causing such rotation, the invention is not limitedin this regard. For instance, as shown in Figure 7, the connectionbetween the parts may be made by forming the upper end of the member G,with an inwardly extending portion 23, of a shape to conform to theflattened portion 22 of the tool, in order that when the tool isproperly seated the sleeve, clamping member and tool will be soconnected as to rotate in unison.

From the foregoing description the operation of the securing means willreadily be undei-stood. When it is desired to introduce, for use, a toolinto the head, to be rotated by the described means, the cap 18 isdepressed, causing the flaring end of the member 6 to protrude beyondthe sleeve 2. In this position the end of the member expands, allowingthe ready introduction of the shank of a tool. The tool is introduced ina position to cause the indentation 22 in the upper end of its shank toreceive the projection 5 extending from the rotatable sleeve 2 andprojecting into the member 6, insuring the positive rotation of the toolwith the parts into which the shank is introduced. When the tool is thuspositioned, pressure on the cap'is released and the spring acts to drawthe flaring end of the member into the sleeve, in which position suchend acts as a clamp to hold the tool against removal.

When the tool is released from the clamp by depressing the cap 18, theeasy removal of the tool is insured, irrespective of the presence ofrust on its shank due to contact with saliva' when in use or of theapplication to it of sterilizing fluid, for the reason that the yfreeingof the clamping end of the member 7 immediately results in its expandingand separating itself from the shank of the tool.

The securing means, which is simple and positive in its operations tohold and release a tool, presents means for securing a tool in place foruse, which is free from the many objections to such means as heretoforeconstructed. Inasmuch as none of the means for holding the tool issubject to wear, the life of the device is practically unlimited.

I claim:

1. A dental handpiece, comprising a rotatable reciprocatorytool-receiving member, means for causing a tool to rotate with themember, the member being provided with means for clamping a tool, and aspring for member being provided with clamping means consisting vof aVflaring compressible portion normally larger than the opening in therotatable sleeve, a springinterposed between the sleeve and thetool-receiving member and acting to drawk the flaring ,portion into thesleeve, and means for `moving the member in a direction opposite to thatinduced by the spring.

4. A dental handpiece, comprising a rotatable sleeve, a reciprocatory`tool-receiving member extending through the sleeve and rotatabletherewith, means for causing a tool to rotate with the member, thetool-receiving *e member being provided with clamping means consistingof a flaring compressible portion,

normally larger than the opening in the rotatable sleeve, and la springfor movingthe tool-receivingmember to operate the clamp- 111g means.

5. A dental handpiece, comprising a ro" tatable sleeve, a reciprocatorytool-receiving member extending through the sleeve and rotatabletherewith, meansfor causing a tool to rotate with the member, thetool-receiving i member being provided with clamping means consistingofy a flaring compressible portion, normally larger than the opening inthe rotatable sleeve, a springiformoving -the toolreceivingmember tooperate the clamping l' means, and a plate contacting with the mem ber,and adapted when pressed to move the .v member ina direction opposite tothat-im-V parted by the spring, for releasing the olamp- Y ing means.

6. A dental handpiece,pcomprising a ro-v tatable sleeve, a reciprocatorytool-receiving member extending through the sleeve and rotatabletherewith, means for causing a tool to rotate withthe member, thetool-receiving member beingprovided with means for engaging a toolhaving a circumferential groove, consisting'k of a flaring compressibleportion, having inwardly extending projections, normally large-r thanthev opening nin *i the rotatable sleeve, and a spring for moving thetool-receiving member to operate theengaging means. n

In testimony whereof YI aHX my signature.

Y PERRYR. SKINNER.

